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US8285155B2 - Optical receiver for the WDM system and method to control the same - Google Patents
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US8285155B2 - Optical receiver for the WDM system and method to control the same - Google Patents

Optical receiver for the WDM system and method to control the same Download PDF

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Publication number
US8285155B2
US8285155B2 US12/631,329 US63132909A US8285155B2 US 8285155 B2 US8285155 B2 US 8285155B2 US 63132909 A US63132909 A US 63132909A US 8285155 B2 US8285155 B2 US 8285155B2
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Prior art keywords
optical
electrical signals
bias current
receiver
current
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US12/631,329
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US20100142958A1 (en
Inventor
Kengo Matsumoto
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Sumitomo Electric Industries Ltd
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Sumitomo Electric Industries Ltd
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Assigned to SUMITOMO ELECTRIC INDUSTRIES, LTD. reassignment SUMITOMO ELECTRIC INDUSTRIES, LTD. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: MATSUMOTO, KENGO
Publication of US20100142958A1 publication Critical patent/US20100142958A1/en
Priority to US13/049,421 priority Critical patent/US8290376B2/en
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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
    • H04B10/07—Arrangements for monitoring or testing transmission systems; Arrangements for fault measurement of transmission systems
    • H04B10/075—Arrangements for monitoring or testing transmission systems; Arrangements for fault measurement of transmission systems using an in-service signal
    • H04B10/079—Arrangements for monitoring or testing transmission systems; Arrangements for fault measurement of transmission systems using an in-service signal using measurements of the data signal
    • H04B10/0795—Performance monitoring; Measurement of transmission parameters
    • H04B10/07955—Monitoring or measuring power
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
    • H04B10/60—Receivers
    • H04B10/66—Non-coherent receivers, e.g. using direct detection
    • H04B10/67—Optical arrangements in the receiver
    • H04B10/671—Optical arrangements in the receiver for controlling the input optical signal
    • H04B10/672—Optical arrangements in the receiver for controlling the input optical signal for controlling the power of the input optical signal
    • H04B10/674—Optical arrangements in the receiver for controlling the input optical signal for controlling the power of the input optical signal using a variable optical attenuator
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
    • H04B10/60—Receivers
    • H04B10/66—Non-coherent receivers, e.g. using direct detection
    • H04B10/69—Electrical arrangements in the receiver
    • H04B10/693—Arrangements for optimizing the preamplifier in the receiver
    • H04B10/6931—Automatic gain control of the preamplifier
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04J—MULTIPLEX COMMUNICATION
    • H04J14/00—Optical multiplex systems
    • H04J14/02—Wavelength-division multiplex systems
    • H04J14/0221—Power control, e.g. to keep the total optical power constant
    • H04J14/02216—Power control, e.g. to keep the total optical power constant by gain equalization

Definitions

  • the present invention relates to an optical receiver applied to the wavelength division multiplexing (WDM) system and a method to control the optical receiver.
  • WDM wavelength division multiplexing
  • the optical receiver modules, 9 a to 9 d convert the de-multiplexed optical signal output from the ODMUX 8 into electrical signals.
  • the optical receiver modules, 9 a to 9 d each accompanies with a receiver circuit in the downstream thereof which may carryout various processes for the electrical signal, for instance, the downstream circuit may carry out the clock recovery, the data recovery and the re-timing of the clock and data.
  • FIG. 1 omits these downstream circuits.
  • the optical receiver modules, 9 a to 9 d may also output the electrical signal to the monitoring unit 10 .
  • the control unit 11 When one of the outputs of the receiver modules, 9 a to 9 d , exceeds the absolute maximum V max or lowers the absolute minimum V min , the control unit 11 outputs the alarm to the outside and ceases the bias current to be supplied to the SOA 7 . A detail of the control for the bias current will be described later.
  • FIG. 4 is a flow chart when the optical receiver 3 is powered on
  • FIG. 5 is a flow chart showing the gain control of the SOA 7 after the optical receiver 3 is powered on.
  • one receiver module shows the output thereof less than the absolute minimum V min , which is the branch “YES” at step S 211 , the arithmetic unit 11 a asserts the alarm to the outside and sets the bias current I b to the initial current I b0 at step S 207 . Finally, the sequence returns to step S 201 to iterate the monitor of the respective outputs of the receiver modules, 9 a to 9 d.
  • the arithmetic unit 11 a increases the bias current I b such that all receiver modules, 9 a to 9 d , show the outputs thereof greater than the lower control limit V cmin .
  • the optical gain of the SOA 7 as shown in FIG. 6 , saturates in a range of a greater bias current. Accordingly, the bias current I b is controlled so as not to exceed the maximum current I bmax .
  • the arithmetic unit 11 a sets the bias current I b to the initial current I b0 when one receiver module shows the output thereof less than the absolute minimum V min , but this absolute minimum V min may be optionally chosen in respective applications based on the relation between the error rate and the OSNR.
  • the optical receiver of the present invention further controls to set the bias current for the SOA in the initial condition I b0 when at least one of the receiver modules, 9 a to 9 d , shows the output thereof out of the absolute minimum V min or the absolute maximum V max . Accordingly, the respective receiver modules may be escaped from the breakdown by the sudden increase of the input optical signal, and from an excessive optical signal after the recover of the optical signal.
  • optical receiver 903 may compact the monitoring unit because of the electrical monitoring arrangement, which also simplifies the optical receiver.

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  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Optical Communication System (AREA)
  • Semiconductor Lasers (AREA)
US12/631,329 2008-12-05 2009-12-04 Optical receiver for the WDM system and method to control the same Active 2030-11-02 US8285155B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US13/049,421 US8290376B2 (en) 2008-12-05 2011-03-16 Optical receiver for the WDM system and the method for controlling the same

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2008-311252 2008-12-05
JP2008311252A JP5223638B2 (ja) 2008-12-05 2008-12-05 光受信モジュールの制御方法

Related Child Applications (1)

Application Number Title Priority Date Filing Date
US13/049,421 Continuation-In-Part US8290376B2 (en) 2008-12-05 2011-03-16 Optical receiver for the WDM system and the method for controlling the same

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US20100142958A1 US20100142958A1 (en) 2010-06-10
US8285155B2 true US8285155B2 (en) 2012-10-09

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JP (1) JP5223638B2 (ja)

Families Citing this family (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5223638B2 (ja) 2008-12-05 2013-06-26 住友電気工業株式会社 光受信モジュールの制御方法
US8290376B2 (en) * 2008-12-05 2012-10-16 Sumitomo Electric Industries, Ltd. Optical receiver for the WDM system and the method for controlling the same
JP5750920B2 (ja) * 2011-02-04 2015-07-22 住友電気工業株式会社 光受信モジュール
JP5667395B2 (ja) 2010-01-25 2015-02-12 富士通株式会社 光受信器
TWI493897B (zh) * 2011-07-05 2015-07-21 Hon Hai Prec Ind Co Ltd 光通訊裝置及光通訊方法
CN102868454B (zh) * 2011-07-05 2016-05-11 鸿富锦精密工业（深圳）有限公司 光通信装置及光通信方法
JP5863172B2 (ja) * 2012-02-22 2016-02-16 富士通株式会社 光受信装置
JP6019704B2 (ja) * 2012-04-24 2016-11-02 住友電気工業株式会社 光送受信装置
JP2013229836A (ja) * 2012-04-27 2013-11-07 Sumitomo Electric Ind Ltd 光送受信装置
JP5884905B2 (ja) * 2012-05-31 2016-03-15 富士通株式会社 光送受信装置および光出力値制御方法
WO2014125647A1 (ja) * 2013-02-18 2014-08-21 富士通オプティカルコンポーネンツ株式会社 光受信装置
JP6127568B2 (ja) * 2013-02-20 2017-05-17 富士通オプティカルコンポーネンツ株式会社 光受信器、光受信方法、および光通信システム
JP6303222B2 (ja) * 2013-11-29 2018-04-04 住友電工デバイス・イノベーション株式会社 光受信器および光受信モジュール
JP2015154186A (ja) 2014-02-13 2015-08-24 富士通オプティカルコンポーネンツ株式会社 光受信装置並びに光受信装置の制御装置及び制御方法
JP6919291B2 (ja) * 2017-04-11 2021-08-18 住友電気工業株式会社 光受信器および光受信器の制御方法
EP4057526B1 (en) * 2019-11-08 2025-10-29 Shimadzu Corporation Optical communication device
JP7722098B2 (ja) * 2021-09-27 2025-08-13 古河ファイテルオプティカルコンポーネンツ株式会社 光受信機、及び光トランシーバモジュール

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Also Published As

Publication number Publication date
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JP2010136195A (ja) 2010-06-17
JP5223638B2 (ja) 2013-06-26

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